Liza Mundy “is an American journalist, non-fiction writer, and fellow at New America Foundation,” and she has deeply researched a matter that had to lie sealed for decades. She has abundantly put to light a crucial course of events from 75 years ago. Here is a book about some women, most of them quite young, who had a hand in shaping the world we know today. The book is aptly titled Code Girls, and it is as much about the coming of American women to intellectual recognition as it is about the herculean task this country committed to the unraveling of enemy intelligence in the Second World War.
Much criticism has been levied against American lack or preparedness in the months leading up to our entry into the war, resoundingly brought to light by the disastrous defeat inflicted by forces of the Japanese Empire on 7 December 1941. All was not fumble-fingers, however. People in critical positions recognized the need for intelligence into Axis powers thinking and movements, and well before we committed to hostilities, the groundwork was being laid that would bring ultimate victory.
The book touches on these early workings, reaching back to the time of the previous war and the American Black Chamber. Herbert O. Yardley was a humble clerk in a government communications bureau 100 years ago when he devised an organization whose work blossomed into America’s modern code breaking and cryptanalysis
The story of women’s involvement with defeating the enemy began in 1916 when a 23-year-old woman, Elizebeth Smith went looking for a job. And, yes, that is the correct spelling of her first name. By one of those quirks of circumstance that shape the universe, she encountered an eccentric Illinois industrialist named George Fabyan.
As luck would have it, there was. It wasn’t at the Newberry, but rather at the estate of a wealthy man named George Fabyan, who was looking for someone to “carry on research” on a literary project involving Sir Francis Bacon. He specifically wanted a woman who was “young, personable, attractive and a good talker.” The librarian called up Fabyan then and there. He had an office in the city, and before long a limousine pulled up, “and in came this whirlwind, this storm, this huge man and his bellowing voice could be heard all over the library floor,” Elizebeth later recalled. Her potential employer was a textile merchant whose family had made a fortune in cotton goods—a hyperactive, wild-eyed person of myriad scientific enthusiasms and no scientific training. Thanks to his wealth, Fabyan was able to indulge his many curiosities. He was incubating any number of so-called research projects at a place he called Riverbank Laboratories, a suburban “think tank” located on an estate in Geneva, Illinois.
Mundy, Liza. Code Girls: The Untold Story of the American Women Code Breakers of World War II (p. 59). Hachette Books. Kindle Edition.
Elizebeth came to work on Fabyan’s project and eventually met her future husband, William Friedman. Of course the Fabyan project proved fruitless, but the task of eking hidden meanings out of mountains of text had the effect of creating America’s pioneering code breakers.
While Yardley’s war efforts were immensely beneficial, they eventually came to an end when newly-confirmed Secretary of State Henry Stimpson put the kibosh on having American intelligence read other people’s communications. Fortunately there were those in Army and Navy intelligence who saw fit to carry on the work somewhat under the table, and as matters in Europe boiled over, the obvious became impossible to ignore. American’s men were going off to fight, and the only people who would be left available to read other people’s mail would be America’s women.
The chain of events that led to the women’s recruitment was a long one, but a signal moment occurred in September 1941, when U.S. Navy rear admiral Leigh Noyes wrote a letter to Ada Comstock, the president of Radcliffe College, the women’s counterpart to Harvard. For more than a year the Navy had been quietly recruiting male intelligence officers from elite colleges and universities, and now it was embarking on the same experiment with women. Noyes wanted to know whether Comstock would identify a group of Radcliffe students to be trained in cryptanalysis. He confided that the Navy was looking for “bright, close-mouthed native students”—that is, high-achieving women who had the sense and ability to keep a secret and who had been born in the United States and were free of close ties with other nations.
Mundy, Liza. Code Girls: The Untold Story of the American Women Code Breakers of World War II (p. 12). Hachette Books. Kindle Edition.
The result was a massive influx of bright, mostly young, women, leaving the farms, leaving low-paying teaching jobs, putting their college education on hold, and boarding trains that would take them to Washington and to places they never knew existed. Eventually their number was in the thousands.
A central point of congregation was the Washington, D.C., area, but another prime destination was Dayton, Ohio, home of National Cash Register. Eighty years ago a cash register was a purely mechanical device (disregarding an embryonic electronic version), and the war effort needed the total output of NCR to be directed toward the war effort. A sales training camp on the outskirts of town was converted into a place where hundreds of Navy women were shipped in by train to assemble and test code-breaking machines called “bombes.” This topic has been previously reviewed:
The team at Bletchley Park, where the British carried out cryptanalysis during the war, was able to crack Enigma codes by feeding message intercepts into an automaton devised by Turing and trying different rotor settings until the output contained legible verbiage. What assisted them throughout the war was incompetence on the part of the German operators. The careless inclusion of expected words allowed the code breakers to vastly narrow their search. Turing’s variable control set allowed adapting the search without reconstructing the machine whenever the Germans made a change in their Enigma.
Enigma was an enciphering-deciphering machine used by the Germans. It employed rotary electric switches to change characters typed into the machine into different characters and back again to produce the original text at the receiving end. This was accomplished in a manner that made it almost impossible to guess the encryption scheme. But Enigma started life as a commercial product, and just about everybody who counted had a copy of the machine. The problem was to figure out which combination of switch settings produced readable German.
This is where the bombe factory came in. American industrial might produced a warehouse full of these bombes for use in trying multiple solutions at a time. The Navy women at the NCR site carefully wired and tested the thousands of components to do the work.
In the Washington area the Navy women (called WAVES) took over Mount Vernon Seminary, and the Army requisitioned suburban Arlington Hall, previously a girls’ school. Suddenly the women were working at well over the pay they had been receiving as school teachers and typists, a difference being whether they worked as civilian employees or members of the newly-created women’s service branches. Civilians received big bucks. The military women got base pay plus military room, board, and medical benefits. For all concerned this would be a life-changing experience.
Cracking of the Enigma code meant the Allies were able to read German naval codes within a few hours of interception. Since the German surface navy retired almost completely from action following the loss of the Graf Spee, decoding Enigma meant hunting down U-boats. In 1942, the months after the United States entered the war, American shipping losses to U-boats were catastrophic. Cracking of the Enigma code, combined with improved detection and attack methods turned 1943 into a death spiral for the U-boat command.
There was always the chance, however, that the U-boats could come back. And they did try. In October 1943, the U-boats reappeared. But now the costs were punishingly high. For every Allied merchant vessel sunk, seven U-boats were lost.
Mundy, Liza. Code Girls: The Untold Story of the American Women Code Breakers of World War II (p. 285). Hachette Books. Kindle Edition.
Toward the end German Admiral Dönitz was sending boats out just to tie up extra Allied resources. Three fourths of German U-boat crew perished in the war.
The Army code-breaking efforts were directed principally toward Japanese messaging. The Japanese used a multiplicity of coding schemes, variously JN – 20, JN – 25, JN – 25A1, and the like. These naval codes were employed increasingly by the Japanese to manage their transport and supply ships, Marus. With the ability to read these messages the American Navy put a strangle-hold on Japanese shipping, sending most of their supply vessels to the bottom of the ocean. Japanese army casualties due to disease and starvation soared as isolated island outposts withered and died.
The intellect of women code breakers was like a thunderclap in a male-dominated world. Some accomplishments were breathtaking:
And there was twenty-seven-year-old Genevieve Marie Grotjan, hired as a “junior cryptanalyst” in October 1939 for a salary of $2,000 per year. It was Grotjan who was standing waiting for the men in the Munitions Building to notice her. A native of Buffalo, New York, Grotjan had been a brilliant all-around student at Buffalo’s Bennett High School, where she delivered the salutatorian’s address in the customary Latin.
Mundy, Liza. Code Girls: The Untold Story of the American Women Code Breakers of World War II (pp. 89-90). Hachette Books. Kindle Edition.
After waiting for the men at the table to notice her, she played the winning hand.
It was September 20, 1940, at around two o’clock in the afternoon. Rowlett, who was one of the more mechanically minded team members—he was a tinkerer and a hoarder and tended to scrounge spare telephone parts, which he kept in his basement behind a woodpile—was talking with some of the other men. Sitting there engrossed in what Rowlett later rather sheepishly called a “gabfest,” they looked up and saw that Genevieve Grotjan, the would-be math teacher and former railway annuity statistician, had materialized beside them. As Rowlett later recalled, she was holding her work sheets clutched to her chest. “Excuse me,” she told them shyly. “I have something to show you.”
Mundy, Liza. Code Girls: The Untold Story of the American Women Code Breakers of World War II (p. 99). Hachette Books. Kindle Edition.
She had cracked the Japanese PURPLE diplomatic code.
The women were recruited without being told what they would be doing. College classes were scanned, course grades were scrutinized, fields of study were examined, lists were drawn up. Women received letters. Come, apply for this job. All they could know was that it was not what they were presently doing, and it had something to do with public service. And it was more money. Once they passed additional screening and before they were informed about the work, they were required to sign a form acknowledging they would be executed if they revealed what they were about to learn. It must have been heady stuff.
They took the jobs for other reasons:
- Some knew they were freeing up men who could then be sent to do the fighting.
- Those who had brothers, boyfriends, almost never husbands, believed that destruction of the enemy would make the men safer.
- It was an intellectual challenge that would otherwise have been denied them.
And still they were people. Some found boyfriends, lovers, husbands. Some became pregnant, which for the military women meant leaving the program. Some broke under the strain of the job. I have no information that any of them broke the vow of silence.
The book is eminently readable, divided into digestible and meaningful chapters. Mundy’s style is easy on the eye, and she is clear and concise. The book shows intense research, providing a level of detail that could not have been obtained without putting in long hours of library research and personal interviews. Highly recommended.
I don’t have a clear idea about when the curtain was pulled from the code-breaking activities of that era, but when David Kahn’s book The Codebreakers came out in 1967 (I have a copy), there were already references to cracking of the Japanese PUPLE code and Enigma.
The code-breaking rooms were vaults of intense concentration, concentration that was broken by frequent looks deeply into the war effort. When Japanese Admiral Isoroku Yamamoto was hunted down and killed using information from the code breakers, they were among the first to know. When their efforts resulted in identifying the route of an enemy ship, the following morning the news reported the ship’s destruction.
As the Nazi empire crumbled, traffic from the European continent dried up, vanishing completely as the last transmitter shut down in early May 1945. A radio intercept operator reported for her shift in August 1945 and was unable to detect any transmissions from the Japanese city of Hiroshima. Following that, day by day, the code breakers eavesdroppers monitored the plaintiff diplomatic traffic as the dying Japanese Empire attempted to salvage something from ten years of war.
Then it was all over. There was no more traffic to decode. Every sender of PURPLE and Enigma was either dead, a prisoner war, or on the run. The women were thanked for their service and shown the door. Some stayed. Some left and later returned. But nobody talked. Women who had husbands returning from the war never told them what they had been doing all the time. The fact is, these women lied about what they did.
If this book is about anything it is a salute to feminism. This cadre of capable women broke the back of the enemy’s communication secrecy and drove a shank into the very gut of conquering armies. Then they were expected to go back home and raise children. It was never going to happen. Along with women industrial workers and along with women who served in the military, some in combat zones, American women were never going back to the kitchen, figuratively speaking.
Even so, the surge was slow to crest. When I entered engineering school 16 years after the war, there were two women in an engineering class of hundreds. I may not have missed the sharp minds other women could have brought, but I, and others, missed having someone besides a couple of guys sitting on either side in class. By the time I went for a graduate degree in computer science 20 years later, women were amply represented. Ten years after that my foray into a physics graduate program was a throwback to the old days. There were women, very sharp but very few. Who’s to figure?
Someone familiar with modern cryptology would be aghast at the primitive methods of 80 years ago. It has to be kept in mind that the 1940s were the days before computers—in fact, code breaking was the impetus for the development of computing machinery. Disguising message contents had either to be done by hand, using code books, look-up tables, and the like, or else the process had to employ electro-mechanical machines like PURPLE or Enigma. Modern encryption leverages off machines such as Enigma. Only a modern computer, or better yet, specialized hardware, can perform the immensely more elaborate scrambling of the text, making the process of winkling out the clear text beyond practicability.
For example, the Diffie-Hellman public key exchange protocol relies on the difficulty of factoring large numbers. Take two prime number, each consisting of 20 decimal digits, for example. Multiply the two numbers to obtain a 21-digit number. The 21-digit number can be public, and if you can factor it, you can crack the key exchange message. Even with a powerful computer this is an intractable task. However, modern computers can perform the computations needed to employ Diffie-Hellman.
The Data Encryption Standard, adopted in 1977, was developed by IBM, and it works by scrambling blocks of text in a reversible manner. This is much along the lines of what Enigma does.
DES is the archetypal block cipher—an algorithm that takes a fixed-length string of plaintext bits and transforms it through a series of complicated operations into another ciphertext bitstring of the same length. In the case of DES, the block size is 64 bits. DES also uses a key to customize the transformation, so that decryption can supposedly only be performed by those who know the particular key used to encrypt. The key ostensibly consists of 64 bits; however, only 56 of these are actually used by the algorithm. Eight bits are used solely for checking parity, and are thereafter discarded. Hence the effective key length is 56 bits.
The National Security Agency (NSA) made recommendations to the key length, and it is assumed the NSA has the ability to crack messages encrypted using the DES.
United States military communications do not use the DES and may be extremely difficult to crack, even with the aid of the world’s most powerful computers. Full disclosure: I have worked with military encryption systems, but I have no inkling of how they work. The SINCGARS radio is such a system:
There have been several system improvement programs, including the Integrated Communications Security (ICOM) models, which have provided integrated voice and data encryption…
SINCGARS, I am told, transmits signals as streams of bits, and it reverses bits in a pseudo-random manner using a process that does not repeat for several years.
Modern cell phones employ Code Division Multiple Access, which does much the same thing. During a session, a cell phone uses its own CDMA channel to communicate with a tower. Communication is by means of bits, which are reversed pseudo-randomly. Your smart TV communicates with your wireless router using this technique. Code breakers of World War Two would have been hard put to crack any of these codes. The process is based on an invention during the war by movie actress Hedy Lamar and others.